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An adaptation in biology is a trait with a current functional role in the life history of an organism that is maintained and evolved by means of natural selection. An adaptation refers to both the current state of being adapted and to the dynamic evolutionary process that leads to the adaptation. Adaptations contribute to the fitness and survival of individuals. Organisms face a succession of environmental challenges as they grow and develop and are equipped with an adaptive plasticity as the phenotype of traits develop in response to the imposed conditions. The developmental norm of reaction for any given trait is essential to the correction of adaptation as it affords a kind of biological insurance or resilience to varying environments.

General principles[link]

The significance of an adaptation can only be understood in relation to the total biology of the species.

— Julian Huxley^[1]

Adaptation is, first of all, a process, rather than a physical part of a body.^[2] An internal parasite (such as a fluke) can illustrate the distinction: such a parasite may have a very simple bodily structure, but nevertheless the organism is highly adapted to its specific environment. From this we see that adaptation is not just a matter of visible traits: in such parasites critical adaptations take place in the life-cycle, which is often quite complex.^[3] However, as a practical term, adaptation is often used for the product: those features of a species which result from the process. Many aspects of an animal or plant can be correctly called adaptations, though there are always some features whose function is in doubt. By using the term adaptation for the evolutionary process, and adaptive trait for the bodily part or function (the product), the two senses of the word may be distinguished.^[4][5][6][7]

Adaptation is one of the two main processes that explain the diverse species we see in biology, such as the different species of Darwin's finches. The other is speciation (species-splitting or cladogenesis), caused by geographical isolation or some other mechanism.^[8][9] A favorite example used today to study the interplay of adaptation and speciation is the evolution of cichlid fish in African lakes, where the question of reproductive isolation is much more complex.^[10][11]

Adaptation is not always a simple matter, where the ideal phenotype evolves for a given external environment. An organism must be viable at all stages of its development and at all stages of its evolution. This places constraints on the evolution of development, behaviour and structure of organisms. The main constraint, over which there has been much debate, is the requirement that each genetic and phenotypic change during evolution should be relatively small, because developmental systems are so complex and interlinked. However, it is not clear what "relatively small" should mean, for example polyploidy in plants is a reasonably common large genetic change.^[12] The origin of the symbiosis of multiple micro-organisms to form a eukaryota is a more exotic example.^[13]

All adaptations help organisms survive in their ecological niches.^[14] These adaptive traits may be structural, behavioral or physiological. Structural adaptations are physical features of an organism (shape, body covering, armament; and also the internal organization). Behavioural adaptations are composed of inherited behaviour chains and/or the ability to learn: behaviours may be inherited in detail (instincts), or a tendency for learning may be inherited (see neuropsychology). Examples: searching for food, mating, vocalizations. Physiological adaptations permit the organism to perform special functions (for instance, making venom, secreting slime, phototropism); but also more general functions such as growth and development, temperature regulation, ionic balance and other aspects of homeostasis. Adaptation, then, affects all aspects of the life of an organism.

Definitions[link]

The following definitions are mainly due to Theodosius Dobzhansky.

1. Adaptation is the evolutionary process whereby an organism becomes better able to live in its habitat or habitats.^[15]

2. Adaptedness is the state of being adapted: the degree to which an organism is able to live and reproduce in a given set of habitats.^[16]

3. An adaptive trait is an aspect of the developmental pattern of the organism which enables or enhances the probability of that organism surviving and reproducing.^[17]

Adaptedness and fitness[link]

From the above definitions, it is clear that there is a relationship between adaptedness and fitness (a key population genetics concept). Differences in fitness between genotypes predict the rate of evolution by natural selection. Natural selection changes the relative frequencies of alternative phenotypes, insofar as they are heritable.^[18] Although the two are connected, the one does not imply the other: a phenotype with high adaptedness may not have high fitness. Dobzhansky mentioned the example of the Californian redwood, which is highly adapted, but a relict species in danger of extinction.^[15] Elliott Sober commented that adaptation was a retrospective concept since it implied something about the history of a trait, whereas fitness predicts a trait's future.^[19]p210

1. Relative fitness. The average contribution to the next generation by a genotype or a class of genotypes, relative to the contributions of other genotypes in the population.^[20]p552 This is also known as Darwinian fitness, selective coefficient, and other terms.

2. Absolute fitness. The absolute contribution to the next generation by a genotype or a class of genotypes. Also known as the Malthusian parameter when applied to the population as a whole.^[18]

3. Adaptedness. The extent to which a phenotype fits its local ecological niche. This can sometimes be tested through a reciprocal transplant experiment.

Brief history[link]

Adaptation as a fact of life has been accepted by many of the great thinkers who have tackled the world of living organisms. It is their explanations of how adaptation arises that separates these thinkers. A few of the most significant ideas:^[21]

• Empedocles did not believe that adaptation required a final cause (~ purpose), but "came about naturally, since such things survived". Aristotle, however, did believe in final causes.
• In natural theology, adaptation was interpreted as the work of a deity, even as evidence for the existence of God.^[22] William Paley believed that organisms were perfectly adapted to the lives they lead, an argument that shadowed Leibniz, who had argued that God had brought about the best of all possible worlds. Voltaire's Dr Pangloss^[23] is a parody of this optimistic idea, and Hume also argued against design.^[24] The Bridgewater Treatises are a product of natural theology, though some of the authors managed to present their work in a fairly neutral manner. The series was lampooned by Robert Knox, who held quasi-evolutionary views, as the Bilgewater Treatises. Darwin broke with the tradition by emphasising the flaws and limitations which occurred in the animal and plant worlds.^[25]

Lamarck

• Lamarck's is a proto-evolutionary theory of the inheritance of acquired traits, whose main purpose is to explain adaptations by natural means.^[26] He proposed a tendency for organisms to become more complex, moving up a ladder of progress, plus "the influence of circumstances", usually expressed as use and disuse. His evolutionary ideas, and those of Geoffroy, fail because they cannot be reconciled with heredity. This was known even before Mendel by medical men interested in human races (Wells, Lawrence), and especially by Weismann.

Many other students of natural history, such as Buffon, accepted adaptation, and some also accepted evolution, without voicing their opinions as to the mechanism. This illustrates the real merit of Darwin and Wallace, and secondary figures such as Bates, for putting forward a mechanism whose significance had only been glimpsed previously. A century later, experimental field studies and breeding experiments by such as Ford and Dobzhansky produced evidence that natural selection was not only the 'engine' behind adaptation, but was a much stronger force than had previously been thought.^[27][28][29]

Types of adaptation[link]

"Adaptation is the heart and soul of evolution." -Niles Eldredge^[30]

Changes in habitat[link]

Before Darwin, adaptation was seen as a fixed relationship between an organism and its habitat. It was not appreciated that as the climate changed, so did the habitat; and as the habitat changed, so did the biota. Also, habitats are subject to changes in their biota: for example, invasions of species from other areas. The relative numbers of species in a given habitat are always changing. Change is the rule, though much depends on the speed and degree of the change.

When the habitat changes, three main things may happen to a resident population: habitat tracking, genetic change or extinction. In fact, all three things may occur in sequence. Of these three effects, only genetic change brings about adaptation.

Habitat tracking[link]

When a habitat changes, the most common thing to happen is that the resident population moves to another locale which suits it; this is the typical response of flying insects or oceanic organisms, who have wide (though not unlimited) opportunity for movement.^[31] This common response is called habitat tracking. It is one explanation put forward for the periods of apparent stasis in the fossil record (the punctuated equilibrium thesis).^[32]

Genetic change[link]

Genetic change is what occurs in a population when natural selection acts on the genetic variability of the population; moreover, some mutations may create genetic variation that will lead to differing characteristics of offspring and hence abet adaptation.^[33] The first pathways of enzyme-based metabolism may have been parts of purine nucleotide metabolism, with previous metabolic pathways being part of the ancient RNA world. By this means, the population adapts genetically to its circumstances.^[34] Genetic changes may result in visible structures, or may adjust physiological activity in a way that suits the changed habitat.

It is now clear that habitats and biota do frequently change. Therefore, it follows that the process of adaptation is never finally complete.^[35] Over time, it may happen that the environment changes little, and the species comes to fit its surroundings better and better. On the other hand, it may happen that changes in the environment occur relatively rapidly, and then the species becomes less and less well adapted. Seen like this, adaptation is a genetic tracking process, which goes on all the time to some extent, but especially when the population cannot or does not move to another, less hostile area. Also, to a greater or lesser extent, the process affects every species in a particular ecosystem.^[36][37]

Van Valen thought that even in a stable environment, competing species had to constantly adapt to maintain their relative standing. This became known as the Red Queen's hypothesis.

Intimate relationships: co-adaptations[link]

In co-evolution, where the existence of one species is tightly over bound up with the life of another species, new or 'improved' adaptations which occur in one species are often followed by the appearance and spread of corresponding features in the other species. There are many examples of this; the idea emphasises that the life and death of living things is intimately connected, not just with the physical environment, but with the life of other species. These relationships are intrinsically dynamic, and may continue on a trajectory for millions of years, as has the relationship between flowering plants and insects (pollination).

Pollinator constancy: these honeybees selectively visit flowers from only one species, as can be seen by the colour of the pollen in their baskets:

• Co-extinction
• Infection-resistance
• Mimicry
• Mutualism
• Parasite-host
• Pollination syndrome
• Predator-prey
• Symbiosis

The gut contents, wing structures, and mouthpart morphologies of fossilized beetles and flies suggest that they acted as early pollinators. The association between beetles and angiosperms during the early Cretaceous period led to parallel radiations of angiosperms and insects into the late Cretaceous. The evolution of nectaries in late Cretaceous flowers signals the beginning of the mutualism between hymenopterans and angiosperms.^[38]

Mimicry[link]

A and B show real wasps; the rest are mimics: three hoverflies and one beetle.

Henry Walter Bates' work on Amazonian butterflies led him to develop the first scientific account of mimicry, especially the kind of mimicry which bears his name: Batesian mimicry.^[39] This is the mimicry by a palatable species of an unpalatable or noxious species. A common example seen in temperate gardens is the hover-fly, many of which – though bearing no sting – mimic the warning colouration of hymenoptera (wasps and bees). Such mimicry does not need to be perfect to improve the survival of the palatable species.^[40]

Bates, Wallace and Müller believed that Batesian and Müllerian mimicry provided evidence for the action of natural selection, a view which is now standard amongst biologists.^[41] All aspects of this situation can be, and have been, the subject of research.^[42] Field and experimental work on these ideas continues to this day; the topic connects strongly to speciation, genetics and development.^[43]

• More on mimicry: Warning Colour and Mimicry Lecture outline from University College London

The basic machinery: internal adaptations[link]

There are some important adaptations to do with the overall coordination of the systems in the body. Such adaptations may have significant consequences. Examples, in vertebrates, would be temperature regulation, or improvements in brain function, or an effective immune system. An example in plants would be the development of the reproductive system in flowering plants.^[44] Such adaptations may make the clade (monophyletic group) more viable in a wide range of habitats. The acquisition of such major adaptations has often served as the spark for adaptive radiation, and huge success over long periods of time for a whole group of animals or plants.

Compromise and conflict between adaptations[link]

"It is a profound truth that Nature does not know best; that genetical evolution... is a story of waste, makeshift, compromise and blunder." -Peter Medawar.^[45]

All adaptations have a downside: horse legs are great for running on grass, but they can't scratch their backs; mammals' hair helps temperature, but offers a niche for ectoparasites; the only flying penguins do is under water. Adaptations serving different functions may be mutually destructive. Compromise and makeshift occur widely, not perfection. Selection pressures pull in different directions, and the adaptation that results is some kind of compromise.^[46]

Since the phenotype as a whole is the target of selection, it is impossible to improve simultaneously all aspects of the phenotype to the same degree. Ernst Mayr.^[47]

Consider the antlers of the Irish elk, (often supposed to be far too large; in deer antler size has an allometric relationship to body size). Obviously antlers serve positively for defence against predators, and to score victories in the annual rut. But they are costly in terms of resource. Their size during the last glacial period presumably depended on the relative gain and loss of reproductive capacity in the population of elks during that time.^[48] Another example: camouflage to avoid detection is destroyed when vivid colors are displayed at mating time. Here the risk to life is counterbalanced by the necessity for reproduction.

An Indian Peacock's train
in full display

The peacock's ornamental train (grown anew in time for each mating season) is a famous adaptation. It must reduce his maneuverability and flight, and is hugely conspicuous; also, its growth costs food resources. Darwin's explanation of its advantage was in terms of sexual selection: "it depends on the advantage which certain individuals have over other individuals of the same sex and species, in exclusive relation to reproduction".^[49] The kind of sexual selection represented by the peacock is called 'mate choice', with an implication that the process selects the more fit over the less fit, and so has survival value.^[50] The recognition of sexual selection was for a long time in abeyance, but has been rehabilitated.^[51] In practice, the blue peafowl Pavo cristatus is a pretty successful species, with a big natural range in India, so the overall outcome of their mating system is quite viable.

The conflict between the size of the human foetal brain at birth, (which cannot be larger than about 400ccs, else it will not get through the mother's pelvis) and the size needed for an adult brain (about 1400ccs), means the brain of a newborn child is quite immature. The most vital things in human life (locomotion, speech) just have to wait while the brain grows and matures. That is the result of the birth compromise. Much of the problem comes from our upright bipedal stance, without which our pelvis could be shaped more suitably for birth. Neanderthals had a similar problem.^[52][53][54]

Shifts in function[link]

Adaptation and function are two aspects of one problem. Julian Huxley^[55]

Pre-adaptations[link]

This occurs when a species or population has characteristics which (by chance) are suited for conditions which have not yet arisen. For example, the polyploid rice-grass Spartina townsendii is better adapted than either of its parent species to their own habitat of saline marsh and mud-flats.^[56] White Leghorn fowl are markedly more resistant to vitamin B deficiency than other breeds.^[57] On a plentiful diet there is no difference, but on a restricted diet this preadaptation could be decisive.

Pre-adaptation may occur because a natural population carries a huge quantity of genetic variability.^[58] In diploid eukaryotes, this is a consequence of the system of sexual reproduction, where mutant alleles get partially shielded, for example, by the selective advantage of heterozygotes. Micro-organisms, with their huge populations, also carry a great deal of genetic variability.

The first experimental evidence of the pre-adaptive nature of genetic variants in micro-organisms was provided by Salvador Luria and Max Delbrück who developed fluctuation analysis, a method to show the random fluctuation of pre-existing genetic changes that conferred resistance to phage in the bacterium Escherichia coli.

Co-option of existing traits: exaptation[link]

The classic example is the ear ossicles of mammals, which we know from palaeontological and embrological studies originated in the upper and lower jaws and the hyoid of their Synapsid ancestors, and further back still were part of the gill arches of early fish.^[59][60] We owe this esoteric knowledge to the comparative anatomists, who, a century ago, were at the cutting edge of evolutionary studies.^[61] The word exaptation was coined to cover these shifts in function, which are surprisingly common in evolutionary history.^[62] The origin of wings from feathers that were originally used for temperature regulation is a more recent discovery (see feathered dinosaurs).

Related issues[link]

Non-adaptive traits[link]

Some traits do not appear to be adaptive, that is, they appear to have a neutral or even deleterious effect on fitness in the current environment. Because genes have pleiotropic effects, not all traits may be functional (i.e. spandrels). Alternatively, a trait may have been adaptive at some point in an organism's evolutionary history, but a change in habitats caused what used to be an adaptation to become unnecessary or even a hindrance (maladaptations). Such adaptations are termed vestigial.

Vestigial organs[link]

Many organisms have vestigial organs, which are the remnants of fully functional structures in their ancestors. As a result of changes in lifestyle the organs became redundant, and are either not functional or reduced in functionality. With the loss of function goes the loss of positive selection, and the subsequent accumulation of deleterious mutations. Since any structure represents some kind of cost to the general economy of the body, an advantage may accrue from their elimination once they are not functional. Examples: wisdom teeth in humans; the loss of pigment and functional eyes in cave fauna; the loss of structure in endoparasites.^[63]

Fitness landscapes[link]

Sewall Wright proposed that populations occupy adaptive peaks on a fitness landscape. In order to evolve to another, higher peak, a population would first have to pass through a valley of maladaptive intermediate stages.^[64] A given population might be "trapped" on a peak that is not optimally adapted.

Extinction[link]

If a population cannot move or change sufficiently to preserve its long-term viability, then obviously, it will become extinct, at least in that locale. The species may or may not survive in other locales. Species extinction occurs when the death rate over the entire species (population, gene pool ...) exceeds the birth rate for a long enough period for the species to disappear. It was an observation of Van Valen that groups of species tend to have a characteristic and fairly regular rate of extinction.^[65]

Co-extinction[link]

Just as we have co-adaptation, there is also co-extinction. Co-extinction refers to the loss of a species due to the extinction of another; for example, the extinction of parasitic insects following the loss of their hosts. Co-extinction can also occur when a flowering plant loses its pollinator, or through the disruption of a food chain.^[66] "Species co-extinction is a manifestation of the interconnectedness of organisms in complex ecosystems ... While co-extinction may not be the most important cause of species extinctions, it is certainly an insidious one".^[67]

Flexibility, acclimatization, learning[link]

Flexibility deals with the relative capacity of an organism to maintain themselves in different habitats: their degree of specialization. Acclimatization is a term used for automatic physiological adjustments during life; learning is the term used for improvement in behavioral performance during life. In biology these terms are preferred, not adaptation, for changes during life which improve the performance of individuals. These adjustments are not inherited genetically by the next generation.

Adaptation, on the other hand, occurs over many generations; it is a gradual process caused by natural selection which changes the genetic make-up of a population so the collective performs better in its niche.

Flexibility[link]

Populations differ in their phenotypic plasticity, which is the ability of an organism with a given genotype to change its phenotype in response to changes in its habitat, or to move to a different habitat.^[68][69]

To a greater or lesser extent, all living things can adjust to circumstances. The degree of flexibility is inherited, and varies to some extent between individuals. A highly specialized animal or plant lives only in a well-defined habitat, eats a specific type of food, and cannot survive if its needs are not met. Many herbivores are like this; extreme examples are koalas which depend on eucalyptus, and pandas which require bamboo. A generalist, on the other hand, eats a range of food, and can survive in many different conditions. Examples are humans, rats, crabs and many carnivores. The tendency to behave in a specialized or exploratory manner is inherited – it is an adaptation.

Rather different is developmental flexibility: "An animal or plant is developmentally flexible if when it is raised or transferred to new conditions it develops so that it is better fitted to survive in the new circumstances".^[70] Once again, there are huge differences between species, and the capacities to be flexible are inherited.

Acclimatization[link]

If humans move to a higher altitude, respiration and physical exertion become a problem, but after spending time in high altitude conditions they acclimatize to the pressure by increasing production of red blood corpuscles. The ability to acclimatize is an adaptation, but not the acclimatization itself. Fecundity goes down, but deaths from some tropical diseases also goes down.

Over a longer period of time, some people will reproduce better at these high altitudes than others. They will contribute more heavily to later generations. Gradually the whole population becomes adapted to the new conditions. This we know takes place, because the performance of long-term communities at higher altitude is significantly better than the performance of new arrivals, even when the new arrivals have had time to make physiological adjustments.^[71]

Some kinds of acclimatization happen so rapidly that they are better called reflexes. The rapid colour changes in some flatfish, cephalopods, chameleons are examples.^[72]

Learning[link]

Social learning is supreme for humans, and is possible for quite a few mammals and birds: of course, that does not involve genetic transmission except to the extent that the capacities are inherited. Similarly, the capacity to learn is an inherited adaptation, but not what is learnt; the capacity for human speech is inherited, but not the details of language.

Function and teleonomy[link]

Adaptation raises some issues concerning how biologists use key terms such as function.

Function[link]

To say something has a function is to say something about what it does for the organism, obviously. It also says something about its history: how it has come about. A heart pumps blood: that is its function. It also emits sound, which is just an ancillary side-effect. That is not its function. The heart has a history (which may be well or poorly understood), and that history is about how natural selection formed and maintained the heart as a pump. Every aspect of an organism that has a function has a history. Now, an adaptation must have a functional history: therefore we expect it must have undergone selection caused by relative survival in its habitat. It would be quite wrong to use the word adaptation about a trait which arose as a by-product.^[73][74]

It is widely regarded as unprofessional for a biologist to say something like "A wing is for flying", although that is their normal function. A biologist would be conscious that sometime in the remote past feathers on a small dinosaur had the function of retaining heat, and that later many wings were not used for flying (e.g. penguins, ostriches). So, the biologist would rather say that the wings on a bird or an insect usually had the function of aiding flight. That would carry the connotation of being an adaptation with a history of evolution by natural selection.

Teleonomy[link]

Teleonomy is a term invented to describe the study of goal-directed functions which are not guided by the conscious forethought of man or any supernatural entity. It is contrasted with Aristotle's teleology, which has connotations of intention, purpose and foresight. Evolution is teleonomic; adaptation hoards hindsight rather than foresight. The following is a definition for its use in biology:

Teleonomy: The hypothesis that adaptations arise without the existence of a prior purpose, but by the action of natural selection on genetic variability.^[75]

The term may have been suggested by Colin Pittendrigh in 1958;^[76] it grew out of cybernetics and self-organising systems. Ernst Mayr, George C. Williams and Jacques Monod picked up the term and used it in evolutionary biology.^{[77][78][79][80]}

Philosophers of science have also commented on the term. Ernest Nagel analysed the concept of goal-directedness in biology;^[81] and David Hull commented on the use of teleology and teleonomy by biologists:

Haldane can be found remarking, "Teleology is like a mistress to a biologist: he cannot live without her but he’s unwilling to be seen with her in public". Today the mistress has become a lawfully wedded wife. Biologists no longer feel obligated to apologize for their use of teleological language; they flaunt it. The only concession which they make to its disreputable past is to rename it ‘teleonomy’.^[82]

See also[link]

Evolutionary biology portal

• Adaptive radiation
• Co-adaptation
• Co-evolution
• Ecological trap
• Evolvability
• Exaptation
• Intragenomic conflict
• Mimicry
• Non-Darwinian Adaptation
• Polymorphism (biology)

References[link]

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Meryl Streep
Meryl Streep in Spain, 2008
Born	Mary Louise Streep (1949-06-22) June 22, 1949 (age 63) Summit, New Jersey, U.S.
Alma mater	Vassar College; Yale School of Drama
Occupation	Actress
Years active	1971–present
Spouse	Don Gummer (m. 1978–present; 4 children)
Partner	John Cazale (1975–1978, his death)
Children	4 (including Mamie Gummer and Grace Gummer)

Mary Louise "Meryl" Streep (born June 22, 1949^[1]) is an American actress who has worked in theatre, television, and film. She is widely regarded as one of the most talented actors of all time.^[2][3][4]

Streep made her professional stage debut in The Playboy of Seville (1971), before her screen debut in the television movie Deadliest Season (1977). In that same year, she made her film debut with Julia (1977). Both critical and commercial success came quickly with roles in The Deer Hunter (1978) and Kramer vs. Kramer (1979), the former giving Streep her first Academy Award nomination and the latter her first win. She later won the Academy Award for Best Actress for her performances in Sophie's Choice (1982) and The Iron Lady (2011).

Streep has received 17 Academy Award nominations, winning three, and 26 Golden Globe nominations, winning eight, more nominations than any other actor in the history of either award. Her work has also earned her two Emmy Awards, two Screen Actors Guild Awards, a Cannes Film Festival award, five New York Film Critics Circle Awards, two BAFTA awards, an Australian Film Institute Award, five Grammy Award nominations, and a Tony Award nomination, amongst others. She was awarded the AFI Life Achievement Award in 2004 and the Kennedy Center Honor in 2009 for her contribution to American culture through performing arts, the youngest actress in each award's history.

Early life and background[link]

Streep was born Mary Louise Streep in Summit, New Jersey.^[5] Her mother, Mary Wolf (née Wilkinson; 1915-2001), was a commercial artist and former art editor, and her father, Harry William Streep, Jr. (1910-2003), was a pharmaceutical executive.^[6][7][8] She has two brothers, Dana David and Harry William III.^[9] Her patrilineal ancestry originates in Loffenau, Germany, from where her second great-grandfather, Gottfried Streeb, emigrated to the United States, and where one of her ancestors served as mayor. Another line of her father's family was from Giswil in the canton of Obwalden, a small town in Switzerland. Her maternal ancestry originates in Pennsylvania and Rhode Island, and partly traces back to 17th century immigrants from England.^[8] Her eighth great-grandfather, Lawrence Wilkinson, was one of the first Europeans to settle Rhode Island. Streep is also a distant relative of William Penn, the founder of Pennsylvania, and records show that her family were among the first purchasers of land in the state.^[10][11][12]

She was raised a Presbyterian,^[13][14] and grew up in Bernardsville, New Jersey, where she attended Bernards High School.^[15] She had many school friends who were Catholic, and regularly attended Mass because she loved its rituals.^[16] She received her B.A., in Drama at Vassar College in 1971 (where she briefly received instruction from actress Jean Arthur), but also enrolled as an exchange student at Dartmouth College for a quarter before it became coeducational. She subsequently earned an M.F.A. from Yale School of Drama. While at Yale, she played a variety of roles onstage,^[17] from the glamorous Helena in A Midsummer Night's Dream to an eighty-year-old woman in a wheelchair in a comedy written by then-unknown playwrights Christopher Durang and Albert Innaurato.^[18][19][20]

Career[link]

Early career[link]

Streep performed in several theater productions in New York and New Jersey after graduating from Yale School of Drama,^[21] including the New York Shakespeare Festival productions of Henry V, The Taming of the Shrew with Raúl Juliá, and Measure for Measure opposite Sam Waterston and John Cazale. She started a relationship with Cazale, and was to live with him until his death three years later. She starred on Broadway in the Brecht/Weill musical Happy End, and won an Obie for her performance in the all-sung off-Broadway production of Alice at the Palace.

Streep by Jack Mitchell

Streep began auditioning for film roles, and later recalled an unsuccessful audition for Dino De Laurentiis for the leading female role in King Kong. De Laurentiis commented to his son in Italian, "She's ugly. Why did you bring me this thing?" and was shocked when Streep replied in fluent Italian.^[22] In New York City, she appeared in the 1976 Broadway double bill of Tennessee Williams' 27 Wagons Full of Cotton and Arthur Miller's A Memory of Two Mondays. For the former, she received a Tony Award nomination for Best Featured Actress in a Play. Her other early Broadway credits include Anton Chekhov's The Cherry Orchard and the Bertolt Brecht-Kurt Weill musical Happy End in which she originally appeared off-Broadway at the Chelsea Theater Center. She received Drama Desk Award nominations for both productions.

Streep's first feature film was Julia (1977), in which she played a small but pivotal role during a flashback scene. Streep was living in New York City with Cazale, who had been diagnosed with bone cancer.^[23] He was cast in The Deer Hunter (1978), and Streep was delighted to secure a small role because it allowed her to remain with Cazale for the duration of filming. She was not specifically interested in the part, commenting, "They needed a girl between the two guys and I was it."^[24]

She played a leading role in the television miniseries Holocaust (1978) as a German woman married to a Jewish artist in Nazi era Germany. She later explained that she had considered the material to be "unrelentingly noble",^[24] and had taken the role only because she had needed money.^[25] Streep travelled to Germany and Austria for filming while Cazale remained in New York. Upon her return, Streep found that Cazale's illness had progressed, and she nursed him until his death on March 12, 1978. She spoke of her grief and her hope that work would provide a diversion; she accepted a role in The Seduction of Joe Tynan (1979) with Alan Alda, later commenting that she played it on "automatic pilot",^[24] and performed the role of Katherine in The Taming of the Shrew for Shakespeare in the Park.^[26] With an estimated audience of 109 million, Holocaust brought a degree of public recognition to Streep, who was described in August 1978 as "on the verge of national visibility".^[25] She won the Primetime Emmy Award for Outstanding Lead Actress – Miniseries or a Movie^[27] for her performance.

The Deer Hunter (1978) was released a month later, and Streep was nominated for the Academy Award for Best Supporting Actress for her performance.

Streep played a supporting role in Manhattan (1979) for Woody Allen, later stating that she had not seen a complete script and was given only the six pages of her own scenes,^[28] and that she had not been permitted to improvise a word of her dialogue.^[29] Asked to comment on the script for Kramer vs. Kramer (1979), in a meeting with the producer Stan Jaffee, director Robert Benton and star Dustin Hoffman, Streep insisted that the female character was not representative of many real women who faced marriage breakdown and child custody battles, and was written as "too evil".^[24] Jaffee, Benton and Hoffman agreed with Streep, and the script was revised.^[24] In preparing for the part, Streep spoke to her own mother about her life as a mother and housewife with a career,^[30] and frequented the Upper East Side neighborhood in which the film was set.^[24] Benton allowed Streep to write her dialogue in two of her key scenes, despite some objection from Hoffman.^[31] Jaffee and Hoffman later spoke of Streep's tirelessness, with Hoffman commenting, "She's extraordinarily hardworking, to the extent that she's obsessive. I think that she thinks about nothing else but what she's doing."^[32]

Streep drew critical acclaim for her performance in each of her three films released in 1979: the romantic comedy Manhattan, the political drama The Seduction of Joe Tynan and the family drama, Kramer vs. Kramer.^[21] She was awarded the Los Angeles Film Critics Association Award for Best Supporting Actress, National Board of Review Award for Best Supporting Actress and National Society of Film Critics Award for Best Supporting Actress for her collective work in the three films. Among the awards won for Kramer vs. Kramer were the Academy Award and Golden Globe Award for Best Supporting Actress.^[21]

1980s[link]

Streep at the 61st Academy Awards, 1989

After prominent supporting roles in two of the 1970s' most successful films, the consecutive winners of the Academy Award for Best Picture, The Deer Hunter and Kramer vs. Kramer, and praise for her versatility in several supporting roles, Streep progressed to leading roles. Her first was The French Lieutenant's Woman (1981). A story within a story drama, the film paired Streep with Jeremy Irons as contemporary actors, telling their modern story as well as the Victorian era drama they were performing. A New York Magazine article commented that, while many female stars of the past had cultivated a singular identity in their films, Streep was a "chameleon", willing to play any type of role.^[33] Streep was awarded a BAFTA Award for Best Actress in a Leading Role for her work.

Her next film, the psychological thriller, Still of the Night (1982) reunited her with Robert Benton, the director of Kramer vs. Kramer, and co-starred Roy Scheider and Jessica Tandy. Vincent Canby, writing for The New York Times, noted that the film was an homage to the works of Alfred Hitchcock, but that one of its main weaknesses was a lack of chemistry between Streep and Scheider, concluding that Streep "is stunning, but she's not on screen anywhere near long enough".^[34]

As the Polish holocaust survivor in Sophie's Choice (1982), Streep's emotional dramatic performance and her apparent mastery of a Polish accent drew praise.^[21] William Styron wrote the novel with Ursula Andress in mind for the part of Sophie, but Streep was very determined to get the role. After she obtained a pirated copy of the script, she went to Alan J. Pakula and threw herself on the ground begging him to give her the part. Streep filmed the "choice" scene in one take and refused to do it again, as she found shooting the scene extremely painful and emotionally exhausting.^[35] Among several notable acting awards, Streep won the Academy Award for Best Actress for her performance. Roger Ebert said of her performance, "Streep plays the Brooklyn scenes with an enchanting Polish-American accent (she has the first accent I've ever wanted to hug), and she plays the flashbacks in subtitled German and Polish. There is hardly an emotion that Streep doesn't touch in this movie, and yet we're never aware of her straining. This is one of the most astonishing and yet one of the most unaffected and natural performances I can imagine."

She followed this success with a biographical film, Silkwood (1983), in which she played her first real-life character, the union activist Karen Silkwood. She discussed her preparation for the role in an interview with Roger Ebert and said that she had met with people close to Silkwood to learn more about her, and in doing so realized that each person saw a different aspect of Silkwood.^[36] Streep concentrated on the events of Silkwood's life and concluded, "I didn't try to turn myself into Karen. I just tried to look at what she did. I put together every piece of information I could find about her... What I finally did was look at the events in her life, and try to understand her from the inside."^[36]

Her next films were a romantic drama, Falling in Love (1984) opposite Robert De Niro, and a British drama, Plenty (1985). Roger Ebert said of Streep's performance in Plenty that she conveyed "great subtlety; it is hard to play an unbalanced, neurotic, self-destructive woman, and do it with such gentleness and charm... Streep creates a whole character around a woman who could have simply been a catalogue of symptoms."^[37]

Out of Africa (1985) starred Streep as the Danish writer Karen Blixen and co-starred Robert Redford. A significant critical success, the film received a 63% "fresh" rating from Rotten Tomatoes.^[38] Streep co-starred with Jack Nicholson in her next two films, the dramas Heartburn (1986) and Ironweed (1987), in which she sang onscreen for the first time since the television movie, Secret Service, in 1977. In A Cry in the Dark (1988), she played the biographical role of Lindy Chamberlain, an Australian woman who had been convicted of the murder of her infant daughter in which Chamberlain claimed her baby had been taken by a dingo. Filmed in Australia, Streep won the Australian Film Institute Award for Best Actress in a Leading Role, a Best Actress at the Cannes Film Festival, the New York Film Critics Circle Award for Best Actress and was nominated for several other awards for her portrayal of Chamberlain.

In She-Devil (1989), Streep played her first comedic film role, opposite Roseanne Barr. Richard Corliss, writing for Time, commented that Streep was the "one reason" to see the film and observed that it marked a departure from the type of role for which she had been known, saying, "Surprise! Inside the Greer Garson roles Streep usually plays, a vixenish Carole Lombard is screaming to be cut loose."^[39]

1990s[link]

From 1984 to 1990, Streep won six People's Choice Awards for Favorite Motion Picture Actress and, in 1990, was named World Favorite.

In the 1990s, Streep continued to choose a great variety of roles, including a drug-addicted movie actress in a screen adaptation of Carrie Fisher's novel Postcards from the Edge, with Dennis Quaid and Shirley MacLaine. Streep and Goldie Hawn had established a friendship and were interested in making a film together. After considering various projects, they decided upon Thelma and Louise, until Streep's pregnancy coincided with the filming schedule, and the producers decided to proceed with Susan Sarandon and Geena Davis.^[22] They subsequently filmed the farcical black comedy, Death Becomes Her, with Bruce Willis as their co-star. Time's Richard Corliss wrote approvingly of Streep's "wicked-witch routine" but dismissed the film as "She-Devil with a make-over".^[40]

Biographer Karen Hollinger describes this period as a downturn in the popularity of Streep's films, which reached its nadir with the failure of Death Becomes Her, attributing this partly to a critical perception that her comedies had been an attempt to convey a lighter image following several serious but commercially unsuccessful dramas, and more significantly to the lack of options available to an actress in her forties.^{[41][clarification needed]} Streep commented that she had limited her options by her preference to work in Los Angeles, close to her family,^[41] a situation that she had anticipated in a 1981 interview when she commented, "By the time an actress hits her mid-forties, no one's interested in her anymore. And if you want to fit a couple of babies into that schedule as well, you've got to pick your parts with great care."^[33]

In 1995, Streep played opposte Clint Eastwood in the love story The Bridges of Madison County (1995). Based on a best-selling novel by Robert James Waller,^[42] it relates the story of Robert Kincaid (Eastwood), a photographer working for National Geographic, who has a love affair with a middle-aged Italian farm wife in Iowa named Francesca (Streep). Streep and Eastwood got along famously during production and such was their on-screen chemistry that a number of people believed that the two were having an affair off-camera, although this was denied by both.^[43] The film was a hit at the box office and grossed $70 million in the United States.^[44] The film, unlike the novel, surprised film critics and was warmly received. Janet Maslin of The New York Times wrote that Clint had managed to create "a moving, elegiac love story at the heart of Mr. Waller's self-congratulatory overkill", while Joe Morgenstern of the The Wall Street Journal described The Bridges of Madison County as "one of the most pleasurable films in recent memory".^[44]

In 1999, Streep portrayed Roberta Guaspari, a real-life New Yorker who found passion and enlightenment teaching violin to inner-city kids in East Harlem, in the music drama Music of the Heart. A departure from director Wes Craven’s previous work on films like A Nightmare on Elm Street and the Scream series, Streep replaced singer Madonna who left the project before filming began due to creative differences with Craven. Required to perform on the violin, Streep went through two months of intense training, four to six hours a day.^[45]

In addition, Streep appeared with Glenn Close in the movie version of Isabel Allende's The House of the Spirits; The River Wild; Marvin's Room (with Diane Keaton and Leonardo DiCaprio); and One True Thing.

2000s[link]

Streep entered the 2000s with Steven Spielberg's A.I. Artificial Intelligence, a science fiction film about a child-like android, played by Haley Joel Osment, uniquely programmed with the ability to love, voicing the Blue Fairy.^[46] The same year, Streep co-hosted the annual Nobel Peace Prize Concert concert with Liam Neeson which was held in Oslo, Norway on December 11, 2001 in honour of the Nobel Peace Prize laureate, the United Nations and Kofi Annan.^[47]

In 2002, Streep returned to the stage for the first time in more than twenty years, playing Arkadina in The Public Theater's revival of Anton Chekhov's The Seagull, directed by Mike Nichols and co-starring Kevin Kline, Natalie Portman, and Philip Seymour Hoffman.^[48] The same year, she began work on Spike Jonze's comedy-drama Adaptation (2002), in which she portrayed real-life journalist Susan Orlean. Lauded by critics and viewers alike,^[49] the film won Streep her fourth Golden Globe in the Best Supporting Actress category.^[50] Also in 2002, Streep appeared alongside Nicole Kidman and Julianne Moore in Stephen Daldry's The Hours, based on the 1999 novel by Michael Cunningham. Focusing on three women of different generations whose lives are interconnected by the novel Mrs. Dalloway by Virginia Woolf, the film was generally well received and won all three leading actresses a Silver Bear for Best Actress the following year.^[50]

Streep in St. Petersburg, Russia in 2004.

The following year, Streep had a cameo as herself in the Farrelly brothers comedy Stuck on You (2003) and reunited with Mike Nichols to star with Al Pacino and Emma Thompson in the HBO adaptation of Tony Kushner's six-hour play Angels in America, the story of two couples whose relationships dissolve amidst the backdrop of Reagan Era politics. Streep, who was cast in four roles in the mini-series, received her second Emmy Award and fifth Golden Globe for her performance.^[50] In 2004, Streep was awarded the AFI Life Achievement Award by the Board of Directors of the American Film Institute,^[50]. She appeared in Jonathan Demme's moderately successful remake of The Manchurian Candidate,^[51] co-starring Denzel Washington, playing the role of a woman who is both a U.S. senator and the manipulative, ruthless mother of a vice-presidential candidate.^[52] The same year, she played the supporting role of Aunt Josephine in Lemony Snicket's A Series of Unfortunate Events alongside Jim Carrey, based on the first three novels in Snicket's book series. The black comedy received generally favorable reviews from critics,^[53] and won the Academy Award for Best Makeup.^[54]

Streep was next cast in the 2005 comedy Prime, directed by Ben Younger. In the film, she played Lisa Metzger, the Jewish psychoanalyst of a divorced and lonesome business-woman, played by Uma Thurman, who enters a relationship with Metzger's 23-year-old son (Bryan Greenberg). A modest mainstream success, it eventually grossed US$67.9 million internationally.^[55] In August and September 2006, she starred onstage at The Public Theater's production of Mother Courage and Her Children at the Delacorte Theatre in Central Park.^[56] The Public Theater production was a new translation by playwright Tony Kushner (Angels in America), with songs in the Weill/Brecht style written by composer Jeanine Tesori (Caroline, or Change); veteran director George C. Wolfe was at the helm. Streep starred alongside Kevin Kline and Austin Pendleton in this three-and-a-half-hour play in which she sang and appeared in almost every scene.

Also in 2006, Streep, along with Lily Tomlin, portrayed the last two members of what was once a popular family country music act in Robert Altman's final film A Prairie Home Companion. A comedic ensemble piece featuring Tommy Lee Jones, Kevin Kline and Woody Harrelson, the film revolves around the behind-the-scenes activities at the long-running public radio show of the same name. The film grossed over US$26 million, the majority of which came from domestic markets.^[57] Commercially, Streep fared better with a role in The Devil Wears Prada (2006), a loose screen adaptation of Lauren Weisberger's 2003 novel of the same name. Streep portrayed the powerful and demanding Miranda Priestly, fashion magazine editor (and boss of a recent college graduate played by Anne Hathaway), and her performance drew rave reviews from critics and earned her many award nominations, including her record-setting 14th Oscar bid, as well as another Golden Globe. Upon its commercial release, the film became Streep's biggest commercial success yet, grossing more than US$326.5 million worldwide.^[58]

In 2007, Streep was cast in four films. She portrayed a wealthy university patron in Chen Shi-zheng's much-delayed feature drama Dark Matter (2007), a film about a Chinese science graduate student who becomes violent after dealing with academic politics at a U.S. university. Inspired by the events of the 1991 University of Iowa shooting,^[59] and initially scheduled for a 2007 release, producers and investors decided to shelve Dark Matter out of respect for the Virginia Tech massacre in April 2007.^[60] The drama received negative to mixed reviews upon its limited 2008 release.^[61] Streep played a U.S. government official who investigates an Egyptian foreign national suspected of terrorism in the political thriller Rendition (2007), directed by Gavin Hood.^[62] Keen to get involved in a thriller film, Streep welcomed the opportunity to star in a film genre for which she was not usually offered scripts and immediately signed on to the project.^[63] Upon its release, Rendition was less commercially successful,^[64] and received mixed reviews.^[65]

Also in 2007, Streep had a short role alongside Vanessa Redgrave, Glenn Close and her eldest daughter Mamie Gummer in Lajos Koltai's drama film Evening, based on the 1998 novel of the same name by Susan Minot. Switching between the present and the past, it tells the story of a bedridden woman, who remembers her tumultuous life in the mid-1950s.^[66] The film was released to lukewarm reactions by critics, who called it "beautifully filmed, but decidedly dull [and] a colossal waste of a talented cast."^[67][68] Streep's last film of 2007 was Robert Redfords Lions for Lambs, a film about the connection between a platoon of United States soldiers in Afghanistan, a U.S. senator, a reporter, and a California college professor.

Streep with her fellow cast and all four members of ABBA at the Swedish premiere of Mamma Mia! in July 2008.

In 2008, Streep found major commercial success when she starred in Phyllida Lloyd's Mamma Mia!, a film adaptation of the musical of the same name, based on the songs of Swedish pop group ABBA. Co-starring Amanda Seyfried, Pierce Brosnan, Stellan Skarsgård and Colin Firth, Streep played a single mother and a former backing singer, whose daughter (Seyfried), a bride-to-be who never met her father, invites three likely paternal candidates to her wedding on an idyllic Greek island.^[69] An instant box office success, Mamma Mia! became Streep's highest-grossing film to date, with box office receipts of US$602.6 million,^[70] also ranking it first among the highest-grossing musical films of all-time.^[71] Nominated for another Golden Globe, Streep's performance was generally well received by critics, with Wesley Morris of the Boston Globe commenting "the greatest actor in American movies has finally become a movie star."^[72] Streep's other film of 2008 was Doubt featuring Philip Seymour Hoffman, Amy Adams, and Viola Davis. A drama revolving around the stern principal nun (Streep) of a Bronx Catholic school in 1964 who brings charges of pedophilia against a popular priest (Hoffman), the film became a moderate box office success,^[73] but was hailed by many critics as one of the best of 2008.^[74] The film received five Academy Awards nominations, for its four lead actors and for Shanley's script.^[50]